Fluid injection tubing with a collar for a test string, having a locking system by abutment against the drilling well head ram

ABSTRACT

For the safety of fluid injection tubes with the shaft head. A fluid injection tube ( 1 ) to be used in safety locking test columns, where a fluid injection tube ( 1 ) is used in a test column (E) of a probing equipment receives a throat ( 6 ) incorporated within its lower edge, right above its nozzle with inner threads ( 5 ). After inserting the test column (E) inside the drilling shaft (P) and coupling the fluid injection tube ( 1 ), as BOP (blow out prevention system) compartments (G) are closed, the throat ( 6 ) is located right below the lower edge of such closed compartments (G). With the fluid injection, if the test column ( 1 ) is pushed and slided upwards, the fluid injection tube ( 1 ) coupled to the shaft is locked by its throat ( 6 ) under the compartments (G) lower edge With this stop locking system between the throat ( 6 ) and compartments (G) edge, the test column (E) is prevented from exceeding the traction force of compartments (G) and being expelled from the probing equipment platform.

The descriptive report hereof refers to a patent of invention request to an adaptation made in a tube, in which a fluid is injected through a drilling shaft test column. This new fluid tube receives a throat and, after being threaded to the threaded box of the upper rod partially exposed in the shaft head, a stopper is formed against the BOP (uncontrolled flow prevention system) closed compartment.

After injecting the fluid, the phase step (where absorption and rock break skill are defined), the pressure applied within the shaft during the test results in an top-bottom force, so then the test column is prevented from expelling by the tube throat locking against the BOP closed compartment lower edge.

TECHNIQUE STATUS

As it is known while shaft drilling in probe system, inasmuch as advancing some layers hit by the chaplet drill shall be tested in a phase called “Absorption Test”. By fluid actions inside the shaft bottom a history shall be defined, which contains soil characteristics for a further analysis by the responsible staff to proceed with drilling operations in compliance to safety standards.

For instance, the patent document PI 8108500-1 so-called “INNER TUBE ELEMENT FOR A PROBING TEST DEVICE AND MANUFACTURING PROCESS OF A LOWER TUBE ELEMENT” may be mentioned, which was requested in Dec. 29, 1981.

To proceed with the test, a tubular column referred as test column is inserted to a drilling shaft, having its upper rod partially exposed in the shaft head with its threaded box placed to screw the threaded nozzle of a fluid injection tube. In the platform, the fluid injection tube in turn gets attached to a pump oversleeve coupling connected to a fluid reservoir, then the referred fluid injection tube is surrounded by the BOP (inflow prevention system and connection between the coating and shaft head), compartment closing, forming a seal over the said shaft head.

After closing BOP compartments surrounding the fluid injection tube, the pump is actuated for such injection, passing test column and going to the shaft bottom, pressurizing it. In this condition, all shaft interior part, as well as the shaft head and BOP, closed by the compartments, undergoes great pressures that are applied from the bottom, which reflects against the test column bottom, forcing it continuously upwards.

Such condition, along with the test column flat wall, help the latter to exceed the locking traction force, formed by closed compartments over the column. When it is pushed upwards, the said test column slides through the surrounding fluid tube passage, as it may move itself regarding its estimated original position in the platform, then risking the test execution and bringing threats to the operation and staff on the operation platform.

PURPOSE OF PATENT

The fluid injection tube here, due to its body adaptation, presents a new locking system that prevents the test column to escape through BOP (Blow out prevention system) compartments under great pressure.

In an overview explanation regarding the fluid injection and its surrounding system, as this patent request purpose, they shall be better detailed in the attached drawings, which describe:

Picture 1—perspective view of the fluid injection tube, showing its upper threaded nozzle to screw the crane connector/lifting system, as well as the fluid input to the pump oversleeve coupling connected to the fluid reservoir. On the lower end of said fluid injection tube, prior to its threaded nozzle (screwed to the threaded box of the test column rod), there is an external throat included, developed for a stop system locking against BOP compartments. In such view, section A-A is indicated;

Picture 2—section A-A;

Picture 3—expanded details A, in a perspective, showing upper and lower-end nozzle of the fluid injection tube;

The following pictures from 4 to 11, in schematic views, refer to the installation of the fluid injection tube and its locking system created for the test column. Both the fluid injection tube and test column rods and drilled shaft have been drawn with its expansion cut and reduced for a better system comprehension:

Picture 4—the shaft drilled by the gas/oil probing system drill column is shown, and along with its head surrounded by the compartments, the test column is being inserted in the test phase to create a history about soil characteristics;

Picture 5—view of the previous picture, which shows the test column being inserted in the shaft;

Picture 6—view of the previous picture, which shows the test column already inserted; The fluid injection tube lower nozzle is screwed by the partially exposed upper threaded box on the shaft head, incorporating the external throat right above. The fluid input is located along with the upper threaded nozzle;

Picture 7—view of the previous picture, showing the closed compartments, incorporating the shaft head and sealing them over the fluid injection tube body. Together with detail B, showing the external throat in an extended manner, incorporated to its lower end, located right below the compartments edge;

Picture 8—view of the previous picture, showing the fluid (due to pump action not shown) is injected, through the oversleeve, fluid input and injection tube cylindrical body, which penetrates in the test column and, eventually in the shaft bottom under pressure;

Picture 9—view of the previous picture, which shows the fluid reaching the shaft head;

Picture 10—view of the previous picture, showing the fluid applying a force from the shaft bottom and pressing the test column coupled to the fluid tube, upwards to the compartment. Together with detail C, showing the pressure and force applied by the fluid through arrows in an extended manner.

Picture 11—view of the previous picture, showing the fluid injection tube pushed upwards with the test column, when the throat is delimited under the lower edge of the compartments, forming a stop locking system along with the latter. In this condition, the test column interrupts its lifting course and it avoids the escape from the compartments and it is expelled from the drilled shaft. This system is shown in detail D in an extended manner.

According to the attached drawings, the FLUID INJECTION TUBE WITH THROAT FOR A TEST COLUMN WITH A STOP LOCKING SYSTEM IN DRILLING SHAFT HEAD COMPARTMENT”, object of this request of patent, is comprised of a fluid injection tube (1) to be used in a test column (E) of the probing equipment, which has an upper end with a threaded nozzle (2) and a head (3) with a fluid input (4). In its lower end, the fluid tube (1) has an internal threaded nozzle (5) and, an external throat (6) is incorporated right above, as shown in pictures 1, 2 and 3.

As the incorporated throat (4) is considered an innovation, the fluid injection tube (1), then providing a new stop locking system to the test column (E) used in the test phase, to create the history for soil characteristics (S) in drilled shafts (P) in gas/oil operations.

As shown in pictures 4 and 5, the test column (E) is guided and inserted through the probing equipment lifting system (not shown) inside the shaft (P), surpassing its head (CA), where BOP (Blow Out prevention system) compartments (G) are installed. The test column (E) partially looses its partially exposed upper rod with a threaded box (C). Afterwards, in its lower end threaded nozzle (5), the fluid injection tube (1) is screwed to the threaded box (C) of the upper rod, coupled to the test column (E), as shown in pictures 6 and 7.

Then the of compartments (G) surrounding the shaft head (P) are closed and faced by their edges on the fluid injection tube body (1), creating a sealing against uncontrolled gas flows. As such, the fluid injection tube (1) throat (6), as especially shown in detail B of picture 7, it is located right below the closed compartments (G) edge.

After receiving it from the fluid input (4), the oversleeve connection (M) of the pump connected to the fluid reservoir (not shown), the test injection is started, as shown in pictures 8 and 9, when the fluid goes through the fluid injection tube (1) and also through the test column (E) until it reaches the shaft bottom (P). In case of great pressures applied by the fluid from the shaft bottom (P), the test column (E) tends to be pushed upwards and it surpasses its traction forces through its smooth walls within itself and the closed BOP compartment, then it slides itself, as it forces its escape through such compartments (C), as shown in picture 10 and its extended detail C.

In this condition, the test column (E) carries the coupled fluid injection tube (1) while lifting, which is locked up under the compartment (G) lower edge with its throat (6), according to the request of patent hereof. As shown in detail D of picture 11, the stop locking system between the throat (6) and compartment (G) lower edges prevents the test column (E) from breaking through the compartment (G) sealing and expelling itself

As the test column (E) is duly locked, the test may be accurately carried out through a sensor system installed in the probe, without impairing the history of soil characteristics regarding the drilled shaft (P) 

1) “FLUID INJECTION TUBE WITH THROAT, FOR A TEST COLUMN”, comprised of a fluid injection tube (1) to be used in a test column (E) of a probing equipment, which has an upper end with a threaded nozzle (2) followed by a head (3) with a fluid input (4), as such fluid tube (1) has an internal threaded nozzle (5) in its lower end, characterized by incorporating a throat (6) externally, right above the latter (5). 2) “STOP LOCKING SYSTEM IN A DRILLING SHAFT HEAD COMPARTMENT”, according to claim 1, after inserting the test column (E) inside the shaft (P), exceeding the shaft head (CA) to be screwed between its threaded box (C) and threaded nozzle (2) of the fluid tube (1), the BOP (blow out uncontrolled flow prevention system) compartment (G) closing is carried out, facing the said fluid injection tube (1) body, which is, in such condition, characterized by positioning its throat (6) right below the closed compartments (G) lower ends. 3) “STOP LOCKING SYSTEM IN A DRILLING SHAFT HEAD COMPARTMENT”, according to claims 1 and 2, after starting the fluid injection, passing the oversleeve (M) through the fluid injection tube (1) and test column (E) until it reaches the shaft bottom (P). If the pressure applied there pushes the test column (E) upwards, that item is delimited in its throat (6) movement while carrying the coupled fluid tube (1), it is characterized by locking the stop under the compartment lower end (G), preventing the said test column (E) to exceed the traction forces between that column and BOP compartments (G), without getting expelled. 